The present invention relates to a liquid crystal panel, a liquid crystal panel cutting method, a liquid crystal panel cutting apparatus and a liquid crystal display device employing the liquid crystal panel.
According to a first prior art techniques as disclosed in Japanese Patent Laid-open No. Hei 7-100799 cuts a liquid crystal panel is cut for a word processor or the like by pressing a rotary blade having a cutting edge of an acute angle nearly equal to a right angle against the liquid crystal panel, and removes a part of the liquid crystal panel on one side of a groove is removed and a crack formed by pressing the rotary blade against the liquid crystal panel by applying an impulsive force to the part of the liquid crystal panel, applying a thermal shock to the liquid crystal panel by heating the liquid crystal panel by a hot plate or applying impulsive vibrations to the liquid crystal panel by a vibrating device.
When the crack cannot be satisfactorily formed, the first prior art technique needs to apply a high shock to the liquid crystal panel. Particularly, when the substrate is a liquid crystal panel formed by combining a top substrate and a bottom substrate, electrodes disposed between the top and the bottom substrate and a sealing resin, stress is induced around the electrodes and the sealing resin when a shock is applied to the liquid crystal panel. Consequently, defects including separation of the sealing resin from the substrates and undesirable breakage off the cutting line are liable to occur. There is the possibility that methods using heat or impulsive vibrations practice the deterioration of durability and performance.
Cutting a liquid crystal panel for a liquid crystal display device is very difficult as compared with cutting a glass plate because the glass substrate comprises a thin glass plate of a thickness of 1 mm or below, and a film of a material softer than glass formed on the thin glass plate. Flexible conductive lines must be affixed to a part of the glass substrate in the vicinity of a cut edge. When the liquid crystal panel is cut mechanically according to the first prior art technique which forms a crack in the liquid crystal panel, the cut liquid crystal panel has a sharp edge, and there is the possibility that the flexible conductive lines that touch the sharp edge of the liquid crystal panel are cut by the sharp edge.
According to a second prior art technique as disclosed in Japanese Patent Laid-open No. Hei 6-305759 a liquid crystal panel has a cut edge formed by cutting the liquid crystal panel by means of a chamfering tool to exclude the possibility.
However, the second prior art technique needs an additional chamfering process and additional time.
Both the first and the second prior art technique are able to cut a liquid crystal panel only along a straight line in a rectangular shape and are incapable of cutting liquid crystal panels in curvilinear shapes to form liquid crystal panel for use on word processors, calculators, traffic signs, toys and illuminations. Thus, the first and the second prior art techniques are inferior in freedom of design.
Accordingly, it is a first object of the present invention to provide a liquid crystal panel capable of preventing damaging flexible conductive lenses without requiring time and labor. A second object of the present invention is to provide a liquid crystal panel cutting method capable of preventing damaging flexible conductive lines by a cut edge of the liquid crystal panel without requiring an additional chamfering process. A third object of the present invention is to provide a liquid crystal panel cutting apparatus capable of carrying out the liquid crystal panel cutting method meeting the second object and of cutting the liquid crystal panel in a curvilinear shape. A fourth object of the present invention is to provide a liquid crystal display device employing the liquid crystal substrate meeting the first object.
A first invention to achieve the first object is a liquid crystal panel comprising a glass substrate cut with a water jet. According to the first invention, when cutting a liquid crystal panel with a water jet as shown in FIGS. 16A and 16B, an edge of an end surface of a glass substrate 31 of the liquid crystal panel is broken into particles 201 of a material forming the edge by the impingement of droplets 200 of a water jet 39 jetted through a nozzle 52 thereon. Therefore, the edge of the end surface is rounded without requiring a chamfering progress and hence damaging flexible conductive lines by the edge of the end surface of the glass substrate can be prevented.
A second invention to achieve the second object is a liquid crystal panel cutting method that cuts a liquid crystal panel by repeatedly blasting liquid droplets or abrasive against a component glass substrate of the liquid crystal panel to crush part of the glass substrate by the impact energy of the liquid droplets or the abrasive. According to the second invention, a liquid crystal panel is cut by repeatedly blasting liquid droplets or abrasive against a component glass substrate of the liquid crystal panel to crush part of the glass substrate by the impact energy of the liquid droplets or the abrasive. The edge of an end surface of the glass substrate is rounded by the impact applied thereto by the liquid droplets or the abrasive. Therefore, flexible conductive lines will not be damaged even if the same come into contact with the edge of the end surface of the glass substrate.
A third invention to achieve the fourth object is a display provided with a liquid crystal panel as a display means, in which the liquid crystal panel has a glass substrate cut with a water jet. According to the third invention, the liquid crystal panel of the display hardly capable of damaging the flexible conductive lines improves the reliability of the display.
A fourth invention to achieve the third object is a liquid crystal panel cutting apparatus comprising a pressure increasing means for increasing the pressure of a liquid, a nozzle provided with a throat that receives the liquid of a pressure produced by the pressure increasing means; a nozzle moving means supporting the nozzle so as to be movable at least in a plane parallel to the liquid crystal panel, and a table supporting the liquid crystal panel. According to the fourth invention, the pressure of the liquid is raised by the pressure increasing means, the liquid is supplied to the nozzle, the flow of the liquid is restricted by the throat and the velocity of the liquid is increased to produce a jet, the jet is applied to the glass substrate of the liquid crystal panel supported on the table, the material of the glass substrate is crushed into particles and removed by the impact energy of the jet of the liquid to cut the glass substrate, and the edge of the cut end surface is rounded by the impact of the liquid thereon to prevent damaging flexible conductive lines when the same touches the edge of the edge surface of the glass substrate. The nozzle is moved in the plane parallel to the liquid crystal panel by the nozzle moving means to cut the liquid crystal panel along a cutting line including curves to form the liquid crystal panel in a desired shape. Thus, the liquid crystal can be formed in a shape of a desired design.
According to a fifth invention, in the liquid crystal panel cutting apparatus according to the fourth invention, the nozzle is provided with an abrasive feed port, and an abrasive fed device for feeding the abrasive is connected to the abrasive feed port to feed the abrasive to the nozzle. The fifth invention has, in addition to the working effects of the fourth invention, a working effect of blasting the abrasive at a high velocity against the glass substrate to crush and remove the material of the glass substrate. Therefore, the glass substrate can be efficiently cut, and the glass substrate can be cut even if the same has a high strength.
According to a sixth invention, in the liquid crystal panel cutting apparatus according to the fourth invention, a plurality of nozzles similar to the foregoing nozzle are supported by a nozzle moving means. Thus, the sixth invention has, in addition to the working effect of the fourth invention, a working effect of simultaneously cutting a plurality of liquid crystal panels corresponding to the plurality of nozzles. Thus, the liquid crystal panel cutting apparatus is suitable for the mass production of liquid crystal panels.
According to a seven invention, in the liquid crystal panel cutting apparatus according to the fourth invention, the liquid in water, alcohol, aceton or kerosene. Thus the seventh invention has, in addition to the working effect of the fourth invention, a working effect of using a liquid selectively determined according to the property of the liquid crystal panel for cutting the liquid crystal panel to suppress the reduction of the strength of the liquid crystal panel to the utmost.
According to an eighth invention, the liquid crystal panel cutting apparatus according to any one of the fourth to the seventh invention further comprises a liquid tank capable of containing the liquid in a depth great enough to immerse the table, the liquid crystal panel, and the nozzle or the nozzles entirely in the liquid, and the table is disposed in the liquid tank so as to be submerged by the liquid. The eighth invention has, in addition to the working effect of any one of the fourth to the seventh invention, a working effect to cut the liquid crystal panel by the jet jetted by the nozzle immersed in the liquid contained in the liquid tank so as to impinge on the liquid crystal panel, leakage of dust produced by the cutting work and noise generated by the cutting work outside the liquid tank can be suppressed. Significant cavitation occurs in the liquid by the jet jetted from the nozzle and cavitation improves cutting efficiency.
According to a ninth invention, the liquid crystal panel cutting apparatus according to any one of the fourth to the seventh invention further comprises a splash guard surrounding the nozzle so as not to block off the path of the jet of the liquid between the nozzle and the liquid crystal panel. The ninth invention has, in addition to the working effect of any one of the fourth to the seventh invention, a working effect to suppress the scatter of chips and particles produced by cutting work to the utmost by the splash guard.
According to a tenth invention, the liquid crystal panel cutting apparatus according to any one of the fourth to the seventh invention further comprises auxiliary nozzles arranged around the nozzle so as not to block at least a path of the jet of the liquid between the nozzle and the liquid crystal panel, and a liquid source connected to the auxiliary nozzles to supply a liquid of a pressure that will not damage the liquid crystal panel to the auxiliary nozzles. The tenth invention has, in addition to the working effect of any one of the fourth to the seventh invention, a working effect of suppressing the scatter of chips and particles produced by the cutting work by surrounding a region in which the cutting work is carried out by jets jetted from the auxiliary nozzles during the cutting work.